Offshore sites, such as offshore wind farms, can prove challenging to establish and/or maintain. The size and complexity of the structures involved, and environmental factors, such as weather and sea conditions, can mean that it can be difficult to construct and/or maintain such sites.
At present, wind turbines and their associated structures are separately constructed onshore, and transported in sections to an offshore site. There, they are moved into position and fixed using slings and cranes. Subsequently, the completed structures are tested.
As the desire for offshore wind farms increases, there is a desire to locate wind turbines structures in deeper water, e.g. deeper than 30 m, such as greater than 45 m. Generally, deeper water sites are further from the shoreline than shallower water sites. Because of the time and complexity involved in establishing sites, such as those in deeper water, the costs can be relatively expensive. In addition, mating of a wind turbine tower with a pre-existing support (e.g. jacket, monopile, transition piece, or the like) has proven challenging, not least of because of the accuracy that is required when aligning a wind turbine tower with that pre-existing support to allow for successful mating of the structures.
In a similar manner, offshore structures not limited to those for use with wind turbines (e.g. jackets, monopiles, oil and gas structures, etc.), are commonly transported to and from offshore sites with the use of cranes, slings, floating crane barges, etc. The use slings and cranes can be hazardous, particularly when the weather conditions are poor.
In addition, when transporting offshore structures—such as wind turbine structures—there is a desire to mitigate, as much as practically possible, inertial effects that arise due to excessive movement. Such inertial effects may cause harm to the structure. For example, it can be desirable when transporting a wind turbine to ensure that the turbine does not experience acceleration (i.e. forces) beyond certain thresholds.
In addition, poor weather conditions can reduce the ability, or at least time window, with which to deploy such offshore structures.
This background serves to set a scene to allow a skilled reader to better appreciate the following description. Therefore, none of the above discussion should necessarily be taken as an acknowledgement that that discussion is part of the state of the art or is common general knowledge. One or more aspects/embodiments of the invention may or may not address one or more of the background issues.